1. Technical Field
This invention relates to shoe sanitizing devices and, more particularly, to a shoe sanitizing device that selectively adjusts output durations of ultraviolet light emitting sources based upon an initial level of microorganisms detected on an exterior shoe sole.
2. Prior Art
It is well-known that exposure to ultraviolet (UV) light of certain wavelengths, intensities, and durations can destroy or inhibit growth of surface pathogens. For instance, germicidal lamps that emit UVC radiation are used to treat waste water for the purpose of reducing organic content. U.S. Pat. Nos. 4,981,651 and 5,978,996 describe the use of UV light for sterilization.
The UV spectrum spans wavelengths from 10 nm to 400 nm. The band from 320 nm to 400 nm is designated as UVA; 280 nm to 320 nm is UVB; and 185 nm to 280 nm is UVC. Germicidal UV light, the type that destroys microorganisms, is limited to a wavelength range from 240 nm to 280 nm, in which maximum germicidal efficiency coincides with a wavelength of 254 nm.
Various methods for disinfecting and removing odor from shoes are known in prior art. These include chemical and physical methods. More specifically, chemical methods include various sprays and shoe liners, while physical include irradiation of the shoe interior by UV light. The methods vary by convenience of application, cost, safety, duration of protection and other features.
The ultraviolet devices appear to be most efficient. However, they suffer from several disadvantages, including difficulty of selectively adjusting a duration of time in which the UV light is transmitted to the shoe. For example, prior art devices deliver UV light to the shoe for a predetermined period of time, regardless of the level of microorganisms located on the shoe. Such prior art shortcomings create the problem of ineffectively disinfecting the shoe and thereby requiring several repeated treatments.
Further, none of prior art eradicates microorganisms from an outer surface of an exterior shoe sole.
Accordingly, a need remains for shoe sanitizing device in order to overcome the above-noted shortcomings. The present invention satisfies such a need by providing a shoe sanitizing device that is convenient and easy to use, is durable yet lightweight in design, is versatile in its applications, and provides a mechanism for selectively adjusting a duration of time in which the UV light is transmitted to the shoe, based upon the microorganism level located on the shoe.